Merge branch '2.1' into 2.2

# Conflicts:
#	gns3server/version.py
#	requirements.txt

gns3server/controller/compute.py

@@ -337,12 +337,13 @@ class Compute:
         return response
 
     @asyncio.coroutine
-    def stream_file(self, project, path):
+    def stream_file(self, project, path, timeout=None):
         """
         Read file of a project and stream it
 
         :param project: A project object
         :param path: The path of the file in the project
+        :param timeout: timeout
         :returns: A file stream
         """
 
@@ -361,7 +362,7 @@ class Compute:
                 self._response.close()
 
         url = self._getUrl("/projects/{}/stream/{}".format(project.id, path))
-        response = yield from self._session().request("GET", url, auth=self._auth, timeout=None)
+        response = yield from self._session().request("GET", url, auth=self._auth, timeout=timeout)
         if response.status == 404:
             raise aiohttp.web.HTTPNotFound(text="{} not found on compute".format(path))
         elif response.status == 403:
@@ -527,8 +528,8 @@ class Compute:
                 headers=headers
             ))
             response = yield from self._session().request(method, url, headers=headers, data=data, auth=self._auth, chunked=chunked, timeout=timeout)
-        except asyncio.TimeoutError as e:
-            raise ComputeError("Timeout error when connecting to {}".format(url))
+        except asyncio.TimeoutError:
+            raise ComputeError("Timeout error for {} call to {} after {}s".format(method, url, timeout))
         except (aiohttp.ClientError, aiohttp.ServerDisconnectedError, ValueError, KeyError, socket.gaierror) as e:
             #  aiohttp 2.3.1 raises socket.gaierror when cannot find host
             raise ComputeError(str(e))
@@ -641,7 +642,7 @@ class Compute:
         List files in the project on computes
         """
         path = "/projects/{}/files".format(project.id)
-        res = yield from self.http_query("GET", path, timeout=120)
+        res = yield from self.http_query("GET", path, timeout=None)
         return res.json
 
     @asyncio.coroutine

gns3server/controller/node.py

@@ -248,6 +248,7 @@ class Node:
 
     @symbol.setter
     def symbol(self, val):
+
         if val is None:
             val = ":/symbols/computer.svg"
 
@@ -261,8 +262,9 @@ class Node:
         self._symbol = val
         try:
             self._width, self._height, filetype = self._project.controller.symbols.get_size(val)
-        # If symbol is invalid we replace it by default
-        except (ValueError, OSError):
+        except (ValueError, OSError) as e:
+            log.error("Could not write symbol: {}".format(e))
+            # If symbol is invalid we replace it by the default
             self.symbol = ":/symbols/computer.svg"
         if self._label is None:
             # Apply to label user style or default
@@ -336,7 +338,7 @@ class Node:
         self._links.remove(link)
 
     @property
-    def link(self):
+    def links(self):
         return self._links
 
     @asyncio.coroutine